var currency = require('./currency'); // 用路径./表明模块跟程序脚本放在同一目录下

console.log('50 Canadian dollars equals this amount of US dollars: ');
console.log(currency.canadianToUS(50)); // 使用currency模块的canadianToUS函数

console.log('30 US dollars equalis this amount of Canadian dollars: ');
console.log(currency.USToCanadian(30)); // 使用currency模块的USToCanadian函数

